Crohn disease

  • Definition
    • Crohn disease is a disease where parts of the digestive tract become inflamed.

      • It most often involves the lower end of the small intestine and the beginning of the large intestine.
      • It may also occur in any part of the digestive system from the mouth to the end of the rectum (anus).

      Crohn disease is a form of inflammatory bowel disease (IBD).

      Ulcerative colitis is a related condition.

      Inflammatory bowel disease
  • Alternative Names
    • Crohn's disease; Inflammatory bowel disease - Crohn's disease; Regional enteritis; Ileitis; Granulomatous ileocolitis; IBD - Crohn's disease

  • Causes
    • The exact cause of Crohn disease is unknown. It occurs when your body's immune system mistakenly attacks and destroys healthy body tissue (autoimmune disorder).

      When parts of the digestive tract remain swollen or inflamed, the walls of the intestines become thickened.

      Factors that may play a role in Crohn disease include:

      • Your genes and family history. (People of Jewish descent are at higher risk.)
      • Environmental factors.
      • Tendency of your body to over-react to normal bacteria in the intestines.
      • Smoking.

      Crohn disease may occur at any age. It most often occurs in people between ages 15 to 35.

  • Symptoms
    • Symptoms depend on what part of the digestive tract is involved. Symptoms range from mild to severe, and can come and go with periods of flare-ups.

      The main symptoms of Crohn disease are:

      • Crampy pain in the abdomen (belly area).
      • Fever.
      • Fatigue.
      • Loss of appetite.
      • Feeling that you need to pass stools, even though your bowels are already empty. It may involve straining, pain, and cramping.
      • Watery diarrhea, which may be bloody.
      • Weight loss.

      Other symptoms may include:

      • Constipation
      • Sores or swelling in the eyes
      • Draining of pus, mucus, or stools from around the rectum or anus (caused by something called a fistula)
      • Joint pain and swelling
      • Mouth ulcers
      • Rectal bleeding and bloody stools
      • Swollen gums
      • Tender, red bumps (nodules) under the skin which may turn into skin ulcers
      Anorectal fistulas
  • Exams and Tests
    • A physical exam may show a mass or tenderness in the abdomen, skin rash, swollen joints, or mouth ulcers.

      Tests to diagnose Crohn disease include:

      • Barium enema or upper GI series
      • Colonoscopy or sigmoidoscopy
      • CT scan of the abdomen
      • Capsule endoscopy
      • MRI of the abdomen
      • Enteroscopy

      A stool culture may be done to rule out other possible causes of the symptoms.

      This disease may also alter the results of the following tests:

      • Low albumin levels
      • High sed rate
      • Fecal fat
      • Low blood count (hemoglobin and hematocrit)
      • Abnormal liver blood tests
      • High white blood cell count
  • Treatment
    • Tips for managing Crohn disease at home:


      You should eat a well-balanced, healthy diet. Include enough calories, protein, and nutrients from a variety of food groups.

      No specific diet has been shown to make Crohn symptoms better or worse. Types of food problems may vary from person to person.

      Some foods can make diarrhea and gas worse. To help ease symptoms, try:

      • Eating small amounts of food throughout the day.
      • Drinking lots of water (drink small amounts often throughout the day).
      • Avoiding high-fiber foods (bran, beans, nuts, seeds, and popcorn).
      • Avoiding fatty, greasy or fried foods and sauces (butter, margarine, and heavy cream).
      • Limiting dairy products if you have problems digesting dairy fats. Try low-lactose cheeses, such as Swiss and cheddar, and an enzyme product, such as Lactaid, to help break down lactose.
      • Avoiding foods that you know cause gas, such as beans.

      Ask your doctor about extra vitamins and minerals you may need, such as:

      • Iron supplements (if you are anemic)
      • Calcium and vitamin D supplements to help keep your bones strong
      • Vitamin B12 to prevent anemia

      If you have an ileostomy, you will need to learn:


      You may feel worried, embarrassed, or even sad and depressed about having a bowel disease. Other stressful events in your life, such as moving, a job loss, or the loss of a loved one can worsen digestive problems.

      Ask your health care provider for tips on how to manage your stress.


      You can take medicine to treat very bad diarrhea. Loperamide (Imodium) can be bought without a prescription. Always talk to your doctor before using these drugs.

      Other medicines to help with symptoms include:

      • Fiber supplements may help your symptoms. You can buy psyllium powder (Metamucil) or methylcellulose (Citrucel). Ask your doctor before taking these products or laxatives.
      • Acetaminophen (Tylenol) for mild pain. Avoid drugs such as aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn) which can make your symptoms worse.

      Your doctor may also prescribe medicines to help control Crohn disease:

      • Aminosalicylates (5-ASAs), medicines that help control mild to moderate symptoms. Some forms of the drug are taken by mouth, and others must be given rectally.
      • Corticosteroids, such as prednisone, treat moderate to severe Crohn disease. They may be taken by mouth or inserted into the rectum.
      • Medicines that quiet the immune system's reaction.
      • Antibiotics to treat abscesses or fistulas.
      • Biologic therapy may be used for severe Crohn disease that does not respond to any other types of medicines.


      Some people with Crohn disease may need surgery to remove a damaged or diseased part of the intestine. In some cases, the entire large intestine is removed, with or without the rectum.

      People who have Crohn disease that does not respond to medicines may need surgery to treat problems such as:

      • Bleeding
      • Failure to grow (in children)
      • Fistulas (abnormal connections between the intestines and another area of the body)
      • Infections
      • Narrowing of the intestine

      Surgeries that may be done include:

      Crohn's Disease Treatment Facts

      1. Crohn's disease can involve the:

        1. A. Large intestine
        2. B. Small intestine
        3. C. Stomach and esophagus
        4. D. Rectum
        5. E. Mouth
        6. F. All of the above

        The correct answer is all of the above. In people with Crohn's disease, the immune system mistakenly attacks the digestive tract--the part of your body that food and waste pass through. This leads to swollen and inflamed tissue, most often in the small intestines. But these changes may occur anywhere from the mouth to the end of the rectum.

      2. Which is NOT a goal of Crohn's disease treatment?

        1. A. Pain relief
        2. B. Weight loss
        3. C. Reduced inflammation
        4. D. Improved nutritional intake

        The correct answer is weight loss. Many people with Crohn's disease lose too much weight, either because of poor appetite or poor absorption of nutrients. The goals of treatment are to reduce inflammation, pain, and diarrhea, and to improve nutrition. Tell your doctor if you're losing weight.

      3. Diet changes are an important part of treating Crohn's disease.

        1. A. True
        2. B. False

        The correct answer is true. No specific diet has been shown to improve Crohn's in everyone. But you can learn to avoid foods that make your symptoms worse. You should eat a well-balanced diet with enough calories, protein, and essential nutrients. Ask your health care provider to help you plan balanced meals.

      4. Which is a good food choice for people with Crohn's disease?

        1. A. Beans
        2. B. Cabbage
        3. C. Broccoli
        4. D. Citrus fruit
        5. E. None of the above

        The correct answer is none of the above. All of these foods can cause gas. Because people with Crohn's are prone to gas, avoiding these foods is a good idea. Talk with your health care provider about which foods are better for people with Crohn's disease.

      5. People with Crohn's disease should eat plenty of fiber.

        1. A. True
        2. B. False

        The correct answer is false. Too much fiber may make your symptoms worse. Try baking or stewing fruits and vegetables if eating them raw bothers you. Eat low-fiber foods if that does not help enough. Ask your doctor about any extra vitamins or mineral supplements you may need.

      6. For mild pain, people with Crohn's disease can take:

        1. A. Acetaminophen
        2. B. Aspirin
        3. C. Ibuprofen
        4. D. Naproxen
        5. E. All of the above

        The correct answer is acetaminophen (Tylenol). It's best to avoid aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn). These medicines may make your symptoms worse. If you have Crohn's disease, check with your doctor before taking any over-the-counter medicines.

      7. Prescription medicines for Crohn's disease can:

        1. A. Reduce swelling and damage in the digestive tract
        2. B. Calm the immune system
        3. C. Both

        The correct answer is both. Some medicines reduce inflammation in the intestines, which can relieve pain and diarrhea. Others keep the immune system from attacking the digestive tract. These medicines can have serious side effects, so talk to your doctor about the pros and cons.

      8. Biologic therapy may help when other treatments don't provide enough relief.

        1. A. True
        2. B. False

        The correct answer is true. Biologic therapies are given by injection. Your doctor may recommend biologic therapy if other medicines don't reduce inflammation enough or if you develop certain complications.

      9. Surgery to remove part of the intestine will cure Crohn's disease.

        1. A. True
        2. B. False

        The correct answer is false. Some people with Crohn's disease may need surgery to remove a damaged part of the intestine or rectum. This can correct bleeding, blockages, and other serious intestinal problems. But it is not a cure. Discuss the risks and benefits of surgery with your doctor.

      10. Patients with Crohn's disease who smoke are more likely to need surgery.

        1. A. True
        2. B. False

        The correct answer is true. Smoking can make Crohn's symptoms worse and increase the chances of needing surgery. Quitting smoking can make Crohn's less severe. Ask your doctor about strategies that can help you quit.

      11. What else can help manage Crohn's disease?

        1. A. Reducing stress
        2. B. Getting enough rest
        3. C. Joining a support group
        4. D. All of the above

        The correct answer is all of the above. Stress can make Crohn's symptoms worse, so it's important to find ways to relax. You may find it helpful to join a support group. The Crohn's and Colitis Foundation of America offers support groups throughout the United States.

  • Support Groups
  • Outlook (Prognosis)
    • There is no cure for Crohn disease. The condition is marked by periods of improvement followed by flare-ups of symptoms. Although Crohn disease cannot be cured even with surgery, treatment can offer significant help to most people.

  • Possible Complications
    • You have a higher risk for small bowel and colon cancer if you have Crohn disease. At some point, your doctor may recommend tests to screen for colon cancer.

      Those with more severe Crohn disease may have these problems:

      • Abscess or infection in the intestines
      • Anemia, a lack of red blood cells
      • Bowel blockage
      • Fistulas in the bladder, skin, or vagina
      • Slow growth and sexual development in children
      • Swelling of the joints
      • Lack of important nutrients, such as vitamin B12 and iron
      • Problems with maintaining a healthy weight
      • Inflammation of the bile ducts (primary sclerosing cholangitis)
  • When to Contact a Medical Professional
    • Call your health care provider if:

      • You have very bad abdominal pain.
      • You cannot control your diarrhea with diet changes and drugs.
      • You have lost weight, or a child is not gaining weight.
      • You have rectal bleeding, drainage, or sores.
      • You have a fever that lasts for more than 2 or 3 days, or a fever higher than 100.4°F (38°C) without an illness.
      • You have nausea and vomiting that lasts for more than a day.
      • You have skin sores that do not heal.
      • You have joint pain that prevents you from doing your everyday activities.
      • You have side effects from medicines you are taking for your condition.
  • References
    • Cheifetz AS. Management of active Crohn disease. JAMA. 2013;309(20):2150-2158. PMID: 23695484

      Fry RD, Mahmoud NN, Maron DJ, Bleier JIS. Colon and rectum. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 52.

      Lichenstein GR. Inflammatory bowel disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 141.

      Lichtenstein GR, Hanauer SB, Sandborn WJ; Practice Parameters Committee of American College of Gastroenterology. Management of Crohn's disease in adults. Am J Gastroenterol. 2009;104(2):465-483. PMID: 19174807

      Sandborn WJ. Crohn's disease evaluation and treatment: clinical decision tool. Gastroenterology. 2014;147(3):702-705. PMID: 25046160

      Sands BE, Siegel CA. Crohn's disease. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 115.

      Terdiman JP, Gruss CB, Heidelbaugh JJ, Sultan S, Falck-Ytter YT; AGA Institute Clinical Practice and Quality Management Committee. American Gastroenterological Association Institute guideline on the use of thiopurines, methotrexate, and anti-TNF-a biologic drugs for the induction and maintenance of remission in inflammatory Crohn's disease. Gastroenterology. 2013;145(6):1459-1463. PMID: 24267474